The present invention relates to power generators, and more particularly, to power generators using the action of water waves.
The ocean is a vast source of energy which goes virtually untapped. In particular, on an average day, thousands of waves move through any given unit area of ocean, and these waves represent a ready and almost limitless supply of energy if the ocean wave can be conveniently translated into usable power.
A prime difficulty with utilizing such wave energy as a power source is that, while an overall wave system may contain a vast amount of energy, each individual wave usually does not have a great deal of available energy. For example, a hectare of ocean may have waves representing an overall total power of many thousands of horsepower while each individual wave may represent only a few thousandths of horsepower. Thus, any mechanical energy transfer means which translates wave motion into usable power must either be extremely large to translate the total power of wave system into usable power, or be very efficient to make use of each individual wave to generate sufficient power to be usable. Therefore, such energy transfer devices can be conveniently catalogued into one of two catagories, large systems which translate a large portion of the total energy of the wave system into usable energy, or small systems which translate the wave energy in only small areas of a total wave system into usable power.
Each class of energy transfer device has its own advantages and disadvantages. For example, those devices falling into the large device catagory are susceptible to damage and/or breakup due to ocean storms or other high wind systems. The larger a device, the more susceptible it is to damage from wind currents or storms. Therefore, those devices falling into the small catagory have an advantage over the large devices by being less susceptible to damage or breakup due to wind currents.
However, those devices catagorized as small devices must make use of the available energy in each wave which is much more efficient than the use made of the energy made of each wave by the large devices.
Efficient usage of wave movement is the very problem which inhibits the wide acceptance of small devices. Due to the design and structure of known devices, the energy which is available in each wave is not efficiently utilized, and therefore, the power output of known devices does not reach a level which is suitable for useful application until the size of the known devices reaches a level approximately that of the large catagory. Therefore, the devices become susceptible to the abovediscussed disadvantages as well as other disadvantages, such as being unsightly and thus detracting from an otherwise scenic beach, or disturbing normal shipping lanes.
One presently known device comprises a plurality of serially connected piston pumps which pressurize a hydraulic fluid for use in a hydraulic energy plant. The pistons of the pumps are connected to floats which are placed in the ocean and which are then rocked by wave movements. The rocking motion of the floats reciprocates the pistons in the pumps to move the fluid through the system. However, each pump utilizes either, but not both, the upward or downward movement of the float resulting from wave motion. Hence, only half of the energy which is available in each wave is utilized to reciprocate the pumps of this system. Therefore, a great number of pumps are utilized to drive the fluid to the system with sufficient pressure to adequately operate the associated power plant. Furthermore, because each pump is driven only by the rocking motion of the floats, without any additional mechanical advantage to increase the pressure in the fluid, this system generally does not pressurize the fluid to a level which is high enough to be usable for large power requirements. To generate such power levels, this device will generally have to be quite large, and therefore, have the drawbacks of the so-called large devices.
Another known device uses first degree levers to reciprocate pumps in response to wave movement. Thus, a pump piston is attached to one end of a lever and a float is attached to the other end. Upward movement of the float causes downward movement of the pump piston to move fluid through the system to a fluid motor. The pumps are ganged together to make full use of a wave front. However, this device, like the device discussed above, utilizes wave movement in only one direction to reciprocate the pump. Thus, only upward movement of the float is utilized to drive fluid through the system. Therefore, even though long levers are used to produce large mechanical advantages, only part of the energy available from each wave is used, and the device must be quite large to produce power levels which are suitable for satisfying large requirements. Therefore, these devices must also be quite large, and hence fall into the so-called large catagory.
The device of the present invention utilizes all of the motion of a float which results from wave movement to reciprocate a pump, and hence makes full use of the available energy in each wave.